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Purpose: The development of tumor vaccines has become a hot topic in immunotherapy for osteosarcoma (OS); however, more tumor antigens with stronger immunogenicity need to be identified. Methods: We downloaded six sets of gene expression profile data from online databases. The overexpressed genes were analyzed, intersected, and used to calculate the immune infiltration abundance in the TARGET OS dataset based on their expression matrix. Potential tumor antigen genes were identified based on whether they exhibited a high correlation with the antigen-presenting cells (APCs). A total of 1330 immune-related genes (IRGs) from the ImmPort website were retrieved based on their expression, and the Consensus Cluster method was used to obtain immune subtypes of the OS samples. Prognosis, immune microenvironment, and sensitivity to drugs were compared among the immune subtypes. Results: In total, 680 genes were overexpressed in at least two datasets, of which TREM2, TNFRSF12A, and THY1 were positively correlated with different APCs. Based on the expression matrix of 1330 IRGs in TARGET-OS, two immune subtypes, IS1 and IS2, were identified. The prognosis of the IS1 subtype was better than that of IS2, the expression of immune checkpoint (ICP)-related genes was higher in patients with the IS1 subtype, and immune cell infiltration and sensitivity to 16 drugs were generally higher in IS1 subtype patients. Conclusion: We identified three APC-correlated genes that can be considered to code for potential novel tumor antigens for OS vaccines. Two immune subtypes in patients with OS were identified to implement personalized treatments using mRNA vaccines.
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Birefringent materials are of great significance to the development of modern optical technology; however, research on halide birefringent crystals with a wide transparent range remains limited. In this work, mercuric bromide (HgBr2) has been investigated for the first time as a promising birefringent material with a wide transparent window spanning from ultraviolet (UV) to far-infrared (far-IR) spectral regions (0.34-22.9 µm). HgBr2 has an exceptionally large birefringence (Δn, 0.235 @ 546 nm), which is 19.6 times that of commercial MgF2. The ordered linear motif [Br-Hg-Br] with high polarizability anisotropy within the molecule is the inherent source of excellent birefringence, making it an efficient building block for birefringent materials. In addition, HgBr2 can be easily grown under mild conditions and remain stable in air for prolonged periods. Studying the birefringent properties of HgBr2 crystals would provide new ideas for future exploration of wide-spectrum birefringent materials.
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Objective: The purpose of this review is to identify the impact of virtual reality (VR) technology on student engagement, specifically cognitive engagement, behavioral engagement, and affective engagement. Methods: A comprehensive search of databases such as Google, Scopus, and Elsevier was conducted to identify English-language articles related to VR and classroom engagement for the period from 2014 to 2023. After systematic screening, 33 articles were finally reviewed. Results: The use of VR in the classroom is expected to improve student engagement and learning outcomes, and is particularly effective for students with learning disabilities. However, introducing VR into middle school education poses several challenges, including difficulties in the education system to keep up with VR developments, increased demands on students' digital literacy, and insufficient proficiency of teachers in using VR. Conclusion: To effectively utilize VR to increase student engagement, we advocate for educational policymakers to provide training and technical support to teachers to ensure that they can fully master and integrate VR to increase student engagement and instructional effectiveness.
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Noncentrosymmetric phosphides have garnered significant attention as promising systems of infrared (IR) nonlinear optical (NLO) materials. Herein, a new quaternary diamond-like phosphide family I-III-IV2-V4 and its inaugural member, namely, CuInSi2P4 (CISP), were successfully fabricated by isovalent and aliovalent substitution based on ZnGeP2. First-principles calculations revealed that CISP has a large NLO coefficient (d14 = 110.8 pm/V), which can be attributed to the well-aligned tetrahedral [CuP4], [InP4], and [SiP4] units. Remarkably, the extremely small thermal expansion anisotropy (0.09) of CISP enables it to exhibit a considerable laser-induced damage threshold (LIDT, 5.0 × AgGaS2@1.06 µm) despite the relatively narrow band gap (0.81 eV). This work improves the chemical diversity of inorganic phosphide and promotes the development of phosphide systems, which may provide valuable perspectives for future exploration of IR NLO materials.
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Feather waste, a rich source of proteins, has traditionally been processed through high-temperature puffing and acid-base hydrolysis, contributing to generation of greenhouse gases and H2S. To address this issue, we employed circular economy techniques to recover the nutritional value of feather waste. Streptomyces sp. SCUT-3, an efficient proteolytic and chitinolytic bacterium, was isolated for feather degradation previously. This study aimed to valorize feather waste for feed purposes by enhancing its feather transformation ability through promoter optimization. Seven promoters were identified through omics analysis and compared to a common Streptomyces promoter ermE*p. The strongest promoter, p24880, effectively enhanced the expression of three candidate keratinases (Sep39, Sep40, and Sep53). The expression efficiency of double-, triple-p24880 and sandwich p24880-sep39-p24880 promoters were further verified. The co-overexpression strain SCUT-3-p24880-sep39-p24880-sep40 exhibited a 16.21-fold increase in keratinase activity compared to the wild-type. Using this strain, a solid-state fermentation process was established that increased the feather/water ratio (w/w) to 1:1.5, shortened the fermentation time to 2.5 days, and increased soluble peptide and free amino acid yields to 0.41 g/g and 0.14 g/g, respectively. The resulting has high protein content (90.49 %), with high in vitro digestibility (94.20 %). This method has the potential to revolutionize the feather waste processing industry.
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Plumas , Streptomyces , Animales , Plumas/química , Streptomyces/genética , Streptomyces/metabolismo , Fermentación , Pollos/metabolismo , Péptido Hidrolasas/genética , Péptido Hidrolasas/química , Queratinas/metabolismo , Concentración de Iones de HidrógenoRESUMEN
Flavobacterium columnare is the causative agent of columnaris disease in freshwater fish. Columnaris disease can cause heavy economic losses in aquaculture. In this study, whole-genome sequencing was used to characterize this pathogen. F. columnare isolate AH-01 had a circular chromosome and plasmid that encoded a total of 3,022 genes. Isolate GX-01 only had a circular chromosome and encoded 2,965 genes. Genomic islands, prophage regions, and CRISPR/Cas systems were identified in both genomes. Both genomes presented evidence of gene variation and horizontal transfer, both of which are the essential components of genetic diversity, genome plasticity, and functional evolution. Single-gene phylogeny and comparative genome analyses were performed to investigate the variation and evolution of this pathogen. Genetic analysis of 16S rRNA and housekeeping gene sequences significantly clustered 55 F. columnare isolates into four clades. The intragroup identity of the 16S rRNA gene exceeded 99%, while the intergroup identity was below the species delineation threshold. We discovered significant translocation, inversion, and rearrangement events that influenced local synteny within each group. Notably, the observed alignments varied considerably among all the studied groups. The core genomes of all strains with available sequences comprised 747 genes, corresponding to approximately 25% of the genome. Core genome multilocus sequence typing, genome-wide orthology and phylogenetic analyses, and average nucleotide identity suggested that the currently existing F. columnare was an assemblage of several distinct species, with levels of divergence at least equivalent to those between recognized bacterial species. The present investigation provided genomic evidence of gene variation and horizontal transfer, which were the basis of genetic diversity, genome plasticity, and functional evolution. The findings supported a proposed new taxonomic perspective on F. columnare.
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Background: Osteoarthritis (OA) progression involves multiple factors, including cartilage erosion as the basic pathological mechanism of degeneration, and is closely related to chondrocyte apoptosis. To analyze the correlation between apoptosis and OA development, we selected apoptosis genes from the differentially expressed genes (DEGs) between OA and normal samples from the Gene Expression Omnibus (GEO) database, used lasso regression analysis to identify characteristic genes, and performed consensus cluster analysis to further explore the pathogenesis of this disease. Methods: The Gene expression profile datasets of OA samples, GSE12021 and GSE55235, were downloaded from GEO. The datasets were combined and analyzed for DEGs. Apoptosis-related genes (ARGs) were collected from the GeneCards database and intersected with DEGs for apoptosis-related DEGs (ARDEGs). Least absolute shrinkage and selection operator (LASSO) regression analysis was performed to obtain characteristic genes, and a nomogram was constructed based on these genes. A consensus cluster analysis was performed to divide the patients into clusters. The immune characteristics, functional enrichment, and immune infiltration statuses of the clusters were compared. In addition, a protein-protein interaction network of mRNA drugs, mRNA-transcription factors (TFs), and mRNA-miRNAs was constructed. Results: A total of 95 DEGs were identified, of which 47 were upregulated and 48 were downregulated, and 31 hub genes were selected as ARDEGs. LASSO regression analysis revealed nine characteristic genes: growth differentiation factor 15 (GDF15), NAMPT, TLR7, CXCL2, KLF2, REV3L, KLF9, THBD, and MTHFD2. Clusters A and B were identified, and neutrophil activation and neutrophil activation involved in the immune response were highly enriched in Cluster B, whereas protein repair and purine salvage signal pathways were enriched in Cluster A. The number of activated natural killer cells in Cluster B was significantly higher than that in Cluster A. GDF15 and KLF9 interacted with 193 and 32 TFs, respectively, and CXCL2 and REV3L interacted with 48 and 82 miRNAs, respectively. Conclusion: ARGs could predict the occurrence of OA and may be related to different degrees of OA progression.
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Apoptosis , MicroARNs , Humanos , Consenso , Apoptosis/genética , MicroARNs/genética , Análisis por Conglomerados , ARN Mensajero , ADN Polimerasa Dirigida por ADN , Proteínas de Unión al ADN , Factores de Transcripción de Tipo KruppelRESUMEN
Cations that can regulate the configuration of anion group are greatly important but regularly unheeded. Herein, the structural transformation from 2D CS to 3D noncentrosymmetric (NCS, which is the prerequisite for second-order NLO effect) is rationally designed to newly afford two sulfides LiMGa8 S14 (M = Rb/Ba, 1; Cs/Ba, 2) by introducing the smallest alkali metal Li+ cation into the interlamination of 2D centrosymmetric (CS) RbGaS2 . The unusual frameworks of 1 and 2 are constructed from C2 -type [Ga4 S11 ] supertetrahedrons in a highly parallel arrangement. 1 and 2 display distinguished NLO performances, including strong phase-matchable second-harmonic generation (SHG) intensities (0.8 and 0.9 × AgGaS2 at 1910 nm), wide optical band gaps (3.24 and 3.32 eV), and low coefficient of thermal expansion for favorable laser-induced damage thresholds (LIDTs, 4.7, and 7.6 × AgGaS2 at 1064 nm), which fulfill the criteria of superior NLO candidates (SHG intensity >0.5 × AGS and band gap >3.0 eV). Remarkably, 1 and 2 melt congruently at 873.8 and 870.5 °C, respectively, which endows them with the potential of growing bulk crystals by the Bridgeman-Stockbarge method. This investigated system provides a new avenue for the structural evolution from layered CS to 3D NCS of NLO materials.
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The SARS-CoV-2 virus that causes COVID-19 is a global health issue. The spread of the virus has resulted in seven million deaths to date. The emergence of new viral strains highlights the importance of continuous surveillance of the SARS-CoV-2 virus by using timely and accurate diagnostic tools. Here, we used a stable cyclic peptide scaffolds to present antigenic sequences derived from the spike protein that are reactive to SARS-CoV-2 antibodies. Using peptide sequences from different domains of SARS-CoV-2 spike proteins, we grafted epitopes on the peptide scaffold sunflower trypsin inhibitor 1 (SFTI-1). These scaffold peptides were then used to develop an ELISA to detect SARS-CoV-2 antibodies in serum. We show that displaying epitopes on the scaffold improves reactivity overall. One of the scaffold peptides (S2_1146-1161_c) has reactivity equal to that of commercial assays, and shows diagnostic potential.
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COVID-19 , Humanos , SARS-CoV-2 , Epítopos , Anticuerpos Antivirales , Péptidos , Péptidos CíclicosRESUMEN
Microorganisms play very important roles in carcinogenesis, tumor progression, and resistance upon treatment. Due to the challenge of accurately acquiring samples and quantifying low-biomass tissue microorganisms, most studies have focused on the effect of gut microorganisms on cancer treatments, especially the efficacy of immunotherapy. Although recent publications reveal the potential interactions between intratumor microorganisms and the immune microenvironment, whether and to what extent the intratumor microorganism could affect progression and treatment outcome remain controversial. This study is aiming to evaluate the associations among intratumor microorganisms, DNA methylation cancer driver genes, immune response, and clinical outcomes from a pan-cancer perspective, using 6,876 TCGA samples across 21 cancer types. We revealed that tumor microorganism dysbiosis is closely associated with the abnormal tumor methylome and/or tumor microenvironment, which might serve to enhance the proliferation ability and fitness for the therapy of tumors. These findings shed the light on a better understanding of the interactions between tumor cells and carcinogens during and after tumor formation, as well as microorganism-associated methylation alterations that could further serve as biomarkers for clinical outcome assessment.
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Metilación de ADN , Neoplasias , Humanos , Neoplasias/patología , Epigenoma , Inmunoterapia , Oncogenes , Microambiente TumoralRESUMEN
The genus Streptomyces comprises the most important chitin decomposers in soil and revealing their chitinolytic machinery is beneficial for the conversion of chitinous wastes. Streptomyces sp. SCUT-3, a chitin-hydrolyzing and a robust feather-degrading bacterium, was isolated previously. The potential chitin-degrading enzymes produced by SCUT-3 were analyzed in the present study. Among these enzymes, three chitinases were successfully expressed in Pichia pastoris at comparatively high yields of 4.8 U/mL (SsExoChi18A), 11.2 U/mL (SsExoChi18B), and 17.8 U/mL (SsEndoChi19). Conserved motifs and constructive 3D structures of these three exo- and endochitinases were also analyzed. These chitinases hydrolyzed colloidal chitin to chitin oligomers. SsExoChi18A showed apparent synergic effects with SsEndoChi19 in colloidal chitin and shrimp shell hydrolysis, with an improvement of 29.3 % and 124.9 %, respectively. Compared with SsExoChi18B and SsEndoChi19, SsExoChi18A exhibited the strongest antifungal effects against four plant pathogens by inhibiting mycelial growth and spore germination. This study provided good candidates for chitinous waste-processing enzymes and antifungal biocontrol agents. These synergic chitin-degrading enzymes of SCUT-3 are good targets for its further genetical modification to construct super chitinous waste-degrading bacteria with strong abilities to hydrolyze both protein and chitin, thereby providing a direction for the future path of the chitinous waste recycling industry.
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Quitinasas , Streptomyces , Quitina/química , Quitinasas/química , Antifúngicos/farmacología , Hongos/metabolismoRESUMEN
Chinese medicine has a long tradition of use against rheumatoid arthritis (RA). The formulations are based on combinations of typically 5-10 plants, which are usually boiled and administered as a decoction or tea. There are few clinical trials performed so the clinical evidence is sparse. One fundamental of traditional medicine is to prevent disease. RA is an autoimmune, inflammatory and chronic disease that primarily affects the joints of 0.5%-1% of the population. In two out of three of the cases, the patients are characterised by the presence of autoantibodies such as the rheumatoid factor and the more disease-specific autoantibody against citrullinated proteins, so-called 'ACPA' (anticitrullinated protein/peptide antibodies). ACPA positivity is also strongly associated with specific variations in the HLA-DRB1 gene, the shared epitope alleles. Together with smoking, these factors account for the major risks of developing RA. In this review, we will summarise the background using certain plant-based formulations based on Chinese traditional medicine for the treatment and prevention of RA and the strategy we have taken to explore the mechanisms of action. We also summarise the major pathophysiological pathways related to RA and how these could be analysed. Finally, we summarise our ideas on how a clinical trial using Chinese herbal medicine to prevent RA could be conducted.
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Artritis Reumatoide , Medicamentos Herbarios Chinos , Alelos , Artritis Reumatoide/tratamiento farmacológico , Artritis Reumatoide/prevención & control , Autoanticuerpos , Ensayos Clínicos como Asunto , Medicamentos Herbarios Chinos/uso terapéutico , Epítopos/genética , Predisposición Genética a la Enfermedad , Cadenas HLA-DRB1/genética , Humanos , Medicina Tradicional China , Péptidos , Factor Reumatoide/genética , TéRESUMEN
Post-embedding correlative light and electron microscopy (CLEM) has the advantage of high-precision registration and enables light and electron microscopy imaging of the same slice. However, its broad application has been hampered by the limited available fluorescent proteins (FPs) and a low signal-to-background ratio (SBR). Here, we developed a green photoswitchable FP, mEosEM-E with substantially high on/off contrast in EM samples embedded in Epon resin, which maximally preserves cellular structures but quenches the fluorescence of FPs. Taking advantage of the photoswitching property of mEosEM-E, the autofluorescence background from the resin was significantly reduced by a subtraction-based CLEM (sCLEM) method. Meanwhile, we identified a red fluorescent protein (RFP) mScarlet-H that exhibited higher brightness and SBR in resin than previously reported RFPs. With mEosEM-E and mScarlet-H, dual-colour post-Epon-embedding CLEM images with high SBR and no cross-talk signal were successfully performed to reveal the organization of nucleolar proteins. Moreover, a dissection of the influences of different EM sample preparation steps on the fluorescence preservation for several RFPs provides useful guidance for further probe development.
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Colorantes , Electrones , Microscopía ElectrónicaRESUMEN
Due to its sensitivity and versatility, fluorescence is widely used to detect specifically labeled biomolecules. However, fluorescence is currently limited by label discrimination, which suffers from the broad full width of the absorption/emission bands and the narrow lifetime distribution of the bright fluorophores. We overcome this limitation by introducing extra kinetic dimensions through illuminations of reversibly photoswitchable fluorophores (RSFs) at different light intensities. In this expanded space, each RSF is characterized by a chromatic aberration-free kinetic fingerprint of photochemical reactivity, which can be recovered with limited hardware, excellent photon budget, and minimal data processing. This fingerprint was used to identify and discriminate up to 20 among 22 spectrally similar reversibly photoswitchable fluorescent proteins (RSFPs) in less than 1s. This strategy opens promising perspectives for expanding the multiplexing capabilities of fluorescence imaging.
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Colorantes Fluorescentes , Imagen Óptica , Cinética , Luz , Microscopía Fluorescente/métodosRESUMEN
The fruits of Physalis (Solanaceae) have a unique structure, a lantern-like fruiting calyx known as inflated calyx syndrome (ICS) or the Chinese lantern, and are rich in steroid-related compounds. However, the genetic variations underlying the origin of these characteristic traits and diversity in Physalis remain largely unknown. Here, we present a high-quality chromosome-level reference genome assembly of Physalis floridana (~1.40 Gb in size) with a contig N50 of ~4.87 Mb. Through evolutionary genomics and experimental approaches, we found that the loss of the SEP-like MADS-box gene MBP21 subclade is likely a key mutation that, together with the previously revealed mutation affecting floral MPF2 expression, might have contributed to the origination of ICS in Physaleae, suggesting that the origination of a morphological novelty may have resulted from an evolutionary scenario in which one mutation compensated for another deleterious mutation. Moreover, the significant expansion of squalene epoxidase genes is potentially associated with the natural variation of steroid-related compounds in Physalis fruits. The results reveal the importance of gene gains (duplication) and/or subsequent losses as genetic bases of the evolution of distinct fruit traits, and the data serve as a valuable resource for the evolutionary genetics and breeding of solanaceous crops.
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Super-resolution fluorescence microscopy, with a spatial resolution beyond the diffraction limit of light, has become an indispensable tool to observe subcellular structures at a nanoscale level. To verify that the super-resolution images reflect the underlying structures of samples, the development of robust and reliable artifact detection methods has received widespread attention. However, the existing artifact detection methods are prone to report false alert artifacts because it relies on absolute intensity mismatch between the wide-field image and resolution rescaled super-resolution image. To solve this problem, we proposed DETECTOR, a structural information-guided artifact detection method for super-resolution images. It detects artifacts by computing the structural dissimilarity between the wide-field image and the resolution rescaled super-resolution image. To focus on structural similarity, we introduce a weight mask to weaken the influence of strong autofluorescence background and proposed a structural similarity index for super-resolution images, named MASK-SSIM. Simulations and experimental results demonstrated that compared with the state-of-the-art methods, DETECTOR has advantages in detecting structural artifacts in super-resolution images. It is especially suitable for wide-field images with strong autofluorescence background and super-resolution images of single molecule localization microscopy (SMLM). DETECTOR has extreme sensitivity to the weak signal region. Moreover, DETECTOR can guide data collection and parameter tuning during image reconstruction.
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KEY MESSAGE: This work reveals potentially multiple and integrated roles in flower and fruit development of floral C-class MADS-box genes in Physalis. The Physalis fruit features a morphological novelty, the Chinese lantern. Floral C-class MADS-domain AGAMOUS-like (AG-like) proteins can interact with the identified regulators of this novel structure. However, the developmental role of the floral C-class genes is unknown in Physalis. Here, we characterized two AG-like genes from Physalis floridana, designated PFAG1 and PFAG2. The two paralogous genes shared around 61.0% of sequence identity and had similar expression domains, with different expression levels in the floral and berry development. However, the genes had distinct expression patterns in leaf and calyx development. Protein-protein interaction analyses revealed that PFAG1 and PFAG2 could commonly or specifically dimerize with certain floral MADS-domain proteins as well as non-MADS-domain proteins involved in various floral developmental processes. Gene downregulation analyses demonstrated that PFAG1 may repress PFAG2, but PFAG2 did not affect PFAG1. Downregulating PFAG1 led to incomplete floral homeotic variation in the stamens and carpels, and alteration of petal coloration pattern, while downregulating PFAG2 did not result in any floral homeotic variation. PFAG1 affected pollen maturation, while PFAG2 affected female fertility. However, simultaneously downregulating PFAG1 and PFAG2 caused loss of the complete C-function, indicating that the two PFAG genes interact to determine the identity and functionality of androecia and gynoecia organs. Their potential roles in regulating fruit size and the Chinese lantern are also discussed. Our results reveal functional divergence of floral C-class MADS-box genes in Physalis, demonstrating that they may play multiple and integrated roles in flower and fruit development.
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Flores/genética , Frutas/genética , Genes de Plantas , Proteínas de Dominio MADS/genética , Physalis/genética , Flores/anatomía & histología , Frutas/anatomía & histología , Regulación de la Expresión Génica de las Plantas , Genotipo , Proteínas de Dominio MADS/metabolismo , Fenotipo , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Mapas de Interacción de Proteínas/genética , Reproducción/genética , Análisis de Secuencia de ADN , Fracciones Subcelulares/metabolismoRESUMEN
Floral B-function MADS-box genes, such as GLOBOSA (GLO), function in corolla and stamen organ identity specification. The functions of these genes outside these floral whorls are rarely reported. DOLL1 is a GLO gene controlling corolla and androecium organ identity. In this study we found that, in Physalis floridana double-layered-lantern 1 (doll1) mutant pollinated with wild-type pollen, fruit set was extremely low, indicating that doll1 females are dysfunctional. Stigma and style structure, stigma receptivity, pollen tube guidance, and embryo sac development were also impaired in doll1. P. floridana CRABS CLAW (PFCRC), predominantly expressed in carpels, was repressed in doll1 native carpels. Loss-of-function of PFCRC altered carpel meristem determinacy, carpel closure, and ovule number, and the resultant 'pistil' consisted of multiple spirally-arranged dorsiventral carpels occasionally with 1-2 naked ovules on the margin and trichomes at each mutated carpel tip, implying an alteration of carpel organ identity. Regulatory and genetic interactions between B-class MADS-box genes and PFCRC were revealed in a context-dependent manner in floral development. Our work reveals a new role for the B-function genes in carpel and ovule development via regulating PFCRC, providing a new understanding of genetic regulatory networks between MADS-domain and CRC transcription factors in mediating carpel organ specification, functionality, and origin.
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Physalis , Flores/genética , Flores/metabolismo , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Proteínas de Dominio MADS/genética , Proteínas de Dominio MADS/metabolismo , Physalis/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismoRESUMEN
The resistance of Lactobacillus plantarum to vancomycin depends on its peptidoglycan composition. Vancomycin has poor binding affinity with peptidoglycan precursors ending in D-alanyl-D-lactate (D-Ala-D-Lac) but binds strongly to peptidoglycan precursors ending in D-alanyl-D-alanine (D-Ala-D-Ala), resulting in resistance and sensitivity, respectively. The ligase Ddl, which generates D-Ala-D-Lac or D-Ala-D-Ala incorporated into the peptidoglycan precursor chain, is responsible for this specificity. To study the effect of peptidoglycan precursors on immunity, we constructed several strains of L. plantarum expressing the ddl gene of Lactococcus lactis to change their peptidoglycan precursors. The change in the termini of the peptidoglycan precursors was determined by the sensitivity of the strains to vancomycin. The overexpression of ddl increased the susceptibility of the strains to vancomycin. We further explored the regulation of the macrophage inflammatory response pathway by the wild-type and constructed strains, and found that these strains induced the MyD88-dependent TRAF6/MAPK pathway, and the increase in D-Ala L. plantarum peptidoglycan precursors increased the secretion of the inflammatory factors IL-6, IL-1ß and TNF-α. These results indicate that D-Ala-ended peptidoglycan precursors play a central role in the variable immunomodulatory ability of L. plantarum.
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Inmunomodulación , Lactobacillus plantarum/inmunología , Peptidoglicano/inmunología , Animales , Antibacterianos/farmacología , Pared Celular/inmunología , Pared Celular/metabolismo , Citocinas/biosíntesis , Dipéptidos/química , Lactobacillus plantarum/genética , Lactobacillus plantarum/metabolismo , Macrófagos/inmunología , Macrófagos/metabolismo , Ratones , Peptidoglicano/química , Probióticos , Células RAW 264.7 , Transducción de Señal , Vancomicina/farmacologíaRESUMEN
Live-cell super-resolution fluorescence microscopy techniques allow biologists to observe subcellular structures, interactions and dynamics at the nanoscale level. Among of them, single molecule-guided Bayesian localization super resolution microscopy (SIMBA) and its derivatives produce an appropriate 50 nm spatial resolution and a 0.1-2s temporal resolution in living cells with simple off-the-shelf total internal reflection fluorescence (TIRF) equipment. However, SIMBA and its derivatives are limited by the requirement for dual-channel dataset or single-channel dataset with special design, the time-consuming calculation for extended field of view and the lack of real-time visualization tool. Here, we propose a universal and accelerated SIMBA ImageJ plug-in, Live-SIMBA, for time-series analysis in living cells. Live-SIMBA circumvents the requirement of dual-channel dataset using intensity-based sampling algorithm and improves the computing speed using multi-core parallel computing technique. Live-SIMBA also better resolves the weak signals inside the specimens with adjustable background estimation and distance-threshold filter. With improved fidelity on reconstructed structures, greatly accelerated computation, and real-time visualization, Live-SIMBA demonstrates its extended capabilities in live-cell super-resolution imaging.